In general, a high quality packaging material is one that creates a good oxygen and moisture barrier. Packaged goods are intended to last longer typically by reducing their interaction with oxygen and water, which usually can deteriorate the product causing waste and other problems. Polymeric materials are often used as packaging materials because they create a good oxygen/moisture barrier and their appearance and shape can be easily controlled. Plastic materials are also used in place of glass for bottling because they are lighter, are more resistant to breakage when dropped, and can be less expensive. Several common polymeric materials used for packaging as well as other uses are polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), polycarbonate (PC), and polystyrene (PS).
Polystyrene is one of the largest volume thermoplastic resins in commercial production today. It is a hydrocarbon chain containing a phenyl group on every other carbon atom. Polystyrene is a durable polymer that is frequently encountered in daily life. A few common examples of polystyrene are plastic toys, computer housings, foam packaging, foam cups, food storage containers, etc.
Polymer nanocomposites comprise polymeric materials and inorganic compounds. When these inorganic components are properly incorporated into a polymer matrix, improvements in physical and mechanical properties can be displayed. The extent of uniformity of distribution of the inorganic compounds incorporated into the polymer matrix influences the characteristics of the nanocomposite.
Also, polystyrene is often times not suitable in certain environments. For example, polystyrene is typically not used in certain heated environments, such as microwave ovens, and may succumb to heat generated therein. It would be desirable to obtain a polystyrene composition that can have higher heat stability and/or higher heat distortion temperatures.